Separation and preconcentration of uranium(VI) from aqueous samples using a surfactant-coated alumina modified with meloxicam

Abstract

A new simple and reliable method for the separation, and preconcentration of trace levels of ions from water samples is developed using a modified sodium dodecyl sulphate (SDS) coated alumina solid phase. The effects of pH, flow rate of sample solution, and foreign ions on the sorption of uranium have been investigated. Twenty micrograms of ions from 1000 mL (pH 5) of aqueous phase could be quantitatively extracted into 1.5 g of meloxicam modified SDS coated alumina. The preconcentration could be made selective to ions by using EDTA as masking agent for transition metal ions and Th(IV). The collected ions were eluted out with 2 mL of HCl solution (1 M) and determined spectrophotometrically using arsenazo(III) as chromogenic reagent. The detection limit corresponding to three times the standard deviation of the blank was found to be 0.52 µg L⁻¹. The relative standard deviation for recovery of 1.0 µg L⁻¹ of ions from water sample (1000 mL) was 3.2% (n = 5). The proposed method was used for the separation of uranium ions from various water samples.

Keywords:

• uranium
• preconcentration
• SDS coated alumina
• meloxicam

Acknowledgement

The authors wish to thank Mr Y. Nikkhahi for his technical assistance.